As international ties have been strengthened on the real economic front, global correlation has been higher in the government bond and other financial markets. Under the circumstances, Japanese banks' market risk associated with holdings of Japanese government bonds (JGBs) has been more susceptible to overseas shocks as well as domestic shocks. Once, for example, overseas government bond markets become volatile, JGB volatility is likely to rise through the market correlation and increase the amount of market risk for Japanese banks. In particular, the regional banks that have been increasing investment in medium- to long-term JGBs have been relatively susceptible to the increased volatility arising from overseas shocks. Banks and other market participants are required to assume various possible channels of shocks and to utilize multiple risk measurement methods including stress testing, thereby grasping market risk from various perspectives.